diff options
| -rw-r--r-- | lib/lib.c | 29 | ||||
| -rw-r--r-- | lib/lib.h | 1 | ||||
| -rwxr-xr-x | tests/ln.test | 10 | ||||
| -rw-r--r-- | toys/posix/ln.c | 27 |
4 files changed, 58 insertions, 9 deletions
@@ -216,6 +216,7 @@ int mkpath(char *dir) } // Split a path into linked list of components, tracking head and tail of list. +// Assigns head of list to *list, returns address of ->next entry to extend list // Filters out // entries with no contents. struct string_list **splitpath(char *path, struct string_list **list) { @@ -1028,6 +1029,34 @@ char *fileunderdir(char *file, char *dir) return rc ? s2 : 0; } +// return (malloced) relative path to get from "from" to "to" +char *relative_path(char *from, char *to) +{ + char *s, *ret = 0; + int i, j, k; + + if (!(from = xabspath(from, -1))) return 0; + if (!(to = xabspath(to, -1))) goto error; + + // skip common directories from root + for (i = j = 0; from[i] && from[i] == to[i]; i++) if (to[i] == '/') j = i+1; + + // count remaining destination directories + for (i = j, k = 0; from[i]; i++) if (from[i] == '/') k++; + + if (!k) ret = xstrdup(to+j); + else { + s = ret = xmprintf("%*c%s", 3*k, ' ', to+j); + while (k--) memcpy(s+3*k, "../", 3); + } + +error: + free(from); + free(to); + + return ret; +} + // Execute a callback for each PID that matches a process name from a list. void names_to_pid(char **names, int (*callback)(pid_t pid, char *name), int scripts) @@ -402,6 +402,7 @@ mode_t string_to_mode(char *mode_str, mode_t base); void mode_to_string(mode_t mode, char *buf); char *getbasename(char *name); char *fileunderdir(char *file, char *dir); +char *relative_path(char *from, char *to); void names_to_pid(char **names, int (*callback)(pid_t pid, char *name), int scripts); diff --git a/tests/ln.test b/tests/ln.test index c326c2e1..6a5787f7 100755 --- a/tests/ln.test +++ b/tests/ln.test @@ -55,6 +55,7 @@ rm -rf file dir slink testing "-t" "ln -st . one/two three && readlink two three" "one/two\nthree\n" \ "" "" +rm -f two three touch file1 file2 && mkdir dir testing "create_multiple_hardlinks" "ln file* dir/ && @@ -78,3 +79,12 @@ testing "create_hardlink_and_remove_sourcefile" "ln file hlink && [ file -ef hlink ] && rm file && [ -f hlink ] && echo 'yes'" \ "yes\n" "" "" rm -f file hlink + +mkdir -p one/two +ln -s . circular +mkdir -p three +echo hello > three/four +testing "ln -r" \ + "ln -sr circular/three/../three/four one/two/five && cat one/two/five" \ + "hello\n" "" "" +rm -rf one three circular diff --git a/toys/posix/ln.c b/toys/posix/ln.c index 306f0cac..3cd5c7b8 100644 --- a/toys/posix/ln.c +++ b/toys/posix/ln.c @@ -4,7 +4,7 @@ * * See http://opengroup.org/onlinepubs/9699919799/utilities/ln.html -USE_LN(NEWTOY(ln, "<1t:Tvnfs", TOYFLAG_BIN)) +USE_LN(NEWTOY(ln, "<1rt:Tvnfs", TOYFLAG_BIN)) config LN bool "ln" @@ -18,6 +18,7 @@ config LN -s Create a symbolic link -f Force the creation of the link, even if TO already exists -n Symlink at TO treated as file + -r Create relative symlink from -> to -t Create links in DIR -T TO always treated as file, max 2 arguments -v Verbose @@ -34,30 +35,37 @@ void ln_main(void) { char *dest = TT.t ? TT.t : toys.optargs[--toys.optc], *new; struct stat buf; - int i; + int i, rc; + + if (FLAG(T) && toys.optc>1) help_exit("Max 2 arguments"); // With one argument, create link in current directory. if (!toys.optc) { toys.optc++; - dest="."; + dest = "."; } - if (FLAG(T) && toys.optc>1) help_exit("Max 2 arguments"); // Is destination a directory? if (!((FLAG(n)||FLAG(T)) ? lstat : stat)(dest, &buf)) { - i = S_ISDIR(buf.st_mode); - - if ((FLAG(T) && i) || (!i && (toys.optc>1 || TT.t))) + if ((i = S_ISDIR(buf.st_mode)) ? FLAG(T) : (toys.optc>1 || TT.t)) error_exit("'%s' %s a directory", dest, i ? "is" : "not"); } else buf.st_mode = 0; for (i=0; i<toys.optc; i++) { - int rc; - char *oldnew, *try = toys.optargs[i]; + char *oldnew = 0, *try = toys.optargs[i]; if (S_ISDIR(buf.st_mode)) new = xmprintf("%s/%s", dest, basename(try)); else new = dest; + if (FLAG(r)) { + try = relative_path(new, try); + if (!try) { + if (new != dest) free(new); + continue; + } + toys.optflags |= FLAG_s; + } + // Force needs to unlink the existing target (if any). Do that by creating // a temp version and renaming it over the old one, so we can retain the // old file in cases we can't replace it (such as hardlink between mounts). @@ -88,6 +96,7 @@ void ln_main(void) FLAG(s) ? "symbolic" : "hard", try, new); else if (FLAG(v)) fprintf(stderr, "'%s' -> '%s'\n", new, try); + if (try != toys.optargs[i]) free(try); if (new != dest) free(new); } } |